A student from Nyeri High School wanted to determine the enthalpy change of combustion when a hydrocarbon with the formula C₆H₁₄ was burnt. The following...

A student from Nyeri High School wanted to determine the enthalpy change of combustion when a hydrocarbon with the formula C₆H₁₄ was burnt. The following are the results of the experiment done.

Mass of water = 100g
Initial temperature = 18.0ºC
Final temperature = 58.0ºC
Mass of the hydrocarbon burned = 0.43g
Specific heat capacity of water = 4.2Jg^-1k^-1

(a) Write a balanced equation for the combustion of the hydrocarbon.
(b) (i) Calculate the amount of heat given out in kJ when 0.43g of the hydrocarbon burn in air.
(ii) Calculate the number of moles of the hydrocarbon that were burnt.
(iii) Calculate the molar enthalpy of combustion of the hydrocarbon.
(c) The theoretical value of the heat released when 1 mole of the hydrocarbon is burnt is 4194.7kJ/mol^-1 Give two reasons why the value obtained from this experiment is less than the theoretical value.

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maurice.mutuku answered the question on September 4, 2019 at 11:07

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